[lld] [lld][riscv] Remove integer check for R_RISCV_SET32 (PR #219143)

[Fangrui Song via llvm-commits]

https://github.com/MaskRay requested changes to this pull request.

the description is missing the context that makes it correct. 
https://github.com/llvm/llvm-project/pull/219532 has a better test

https://github.com/llvm/llvm-project/pull/219143